How to Dynamically Update Shared Paths on an NFS File System

You can
dynamically modify the shared paths on an NFS file system without bringing
offline the Sun Cluster HA for NFS resource. The general procedure consists of modifying
the dfstab.resource file for Sun Cluster HA for NFS
and then manually running the appropriate command, either the share command or the unshare command. The command
is immediately effective, and Sun Cluster HA for NFS handles making these paths highly
available.

Ensure that the paths that are shared are always available to Sun Cluster HA for NFS
during failover so that local paths (on non-HA file systems) are not used.

If paths on a file system that is managed by HAStoragePlus are shared,
the HAStoragePlus resource must be in the same resource group as the Sun Cluster HA for NFS
resource, and the dependency between them must be set correctly.

Use the scstat -g command to find out the node on
which the Sun Cluster HA for NFS resource is online.

On this node run the /usr/sbin/share command to see
the list of paths currently shared. Determine the changes you want to make
to this list.

To add a new shared path, perform the following steps.

Add the share command to the dfstab.resource file.

Sun Cluster HA for NFS shares the new path the next time it checks the file. The
frequency of these checks is controlled by the Thorough_Probe_Interval property (by default 120 seconds).

Run the share command manually to make
the newly added shared path effective immediately. Running the command manually
is recommended because the user can be certain that the shared paths are
available to potential clients. Sun Cluster HA for NFS detects that the newly added path
is already shared and does not complain.

To unshare a path, perform the following steps.

Run the dfmounts(1M) command to ensure
that no clients are currently using the path.

Although a path can be unshared even if clients are using it, these
clients would get a stale file error handle and would need special care (forced
umount, or even reboot) to recover.

Remove the shared path from the dfstab.resource file.

Run the unshare command manually.

To modify options for an existing shared path, perform the following
steps.